Laravel notifications - how to use custom type

AppServiceProvider.php

<?php

namespace App\Providers;

use App\Notifications\DatabaseChannel as CustomDatabaseChannel;
use Illuminate\Notifications\Channels\DatabaseChannel;
use Illuminate\Support\ServiceProvider;

class AppServiceProvider extends ServiceProvider
{
    /**
     * Register any application services.
     *
     * @return void
     */
    public function register()
    {
        $this->app->bind(
            DatabaseChannel::class,
            CustomDatabaseChannel::class
        );
    }

    /**
     * Bootstrap any application services.
     *
     * @return void
     */
    public function boot()
    {
        //
    }
}

DatabaseChannel.php

<?php

namespace App\Notifications;

use Illuminate\Notifications\Channels\DatabaseChannel as Channel;
use Illuminate\Notifications\Notification;

class DatabaseChannel extends Channel
{
    protected function buildPayload($notifiable, Notification $notification)
    {
        return ['type' => $notification->type ?? get_class($notification)]
            + parent::buildPayload($notifiable, $notification);
    }
}